Device for unloading packaged merchandise



Dec. 3, 1946. P. JESSEN 2,412,155

DEVICE FOR UNLOADING PACKAGED MERCHANDISE Filed Sept. 27, 194A 5Sheets-Sheet 1 Elli B INVENTOR.

PP/FBE/V JESSE/V Dec. 3, 1946. P. JESSEN 2,412,155

DEVICE FOR UNLOADING PACKAGED MERCHANDISE Filed Sept. 27, 1944 i 5Sheets-Sheet 2 INVENTOR.

PKEBM JESSE/V Dec. 3, 1946. P. JESSEN 2,412,155

DEVICE FOR UNLCADING PACKAGED MERCHANDISE ,Filed Sept. 27, 1944 5Sheets-Sheet 3 PREBEN J15 1365 INVENTOR.

Dec. 3, 1946. JESSEN 2,412,155

DEVICE FORUNLOADING PACKAGED MERCHANDISE Filed Sept. 27, 1944 5Sheets-Sheet 4 PREBM Jfssm VEN dwiwyggz Dec. 3, 1946. P. JESSEN2,412,155

DEVICE FOR UNLOADING PACKAGED MERCHANDISE File'd'Sept. 27, 1944 '5Sheets-Sheet 5 /62 E IE .ZEI INVENTOR.

PREBE/V ff 55f jmaww Patented Dec. 3, 1946 UNITED STATES PATENT OFFICEnrvrcs rounmanme racxaonn ISB Preben Jesen, North Be l N. J.

7 Application September 27, 1944, Serial No. 556,011

2 Claim (Cl- 214-82) This invention relata to improvements in industrlaltrucks for use in handling, loading, unloading and stacking packagedgoods and materials. The object of the invention is to provide anindustrial fork truck with a novel and improved mechanism for dischar gthe load whereby to efl'ect important savings in time, labor andoperating costs in handling packaged material. The said noveldischarging m is embodied in a collapsible platform which is carried bythe truck together with automatic operating means for positioning saidplatform to receive the load from the truck and deposit the load uponthe floor or upon a previously deposited load as the case may be. Thecollapsible platform may also be used as an independent unloading deviceapart from the truck. In either case, an entirely novel method indischarging and depositing packaged material is involved as a feature ofthe invention.

The industrial truck is disclosed herein in connection with the handlingof packaged material supported upon pallets, skids or the like. The useof the collapsible platform apart from the truck is also disclosed. Thedetailed construction, mode of operation and the several features of theinvention are set forth in the following specification and illustratedin the accompanying drawings in which Figs. 1 to 5 illustratediagrammatically the 30 Fig. 12 is a detail view of the platform oper- 5ating cylinder with parts in section.

Fig. 13 is a detail plan view, partly in section, showing the cradlemechanism which contains and supports the platform and the means forexpelling the platform from the cradle.

Fig.14isasectionalviewontheline of Fig. 13.

Fig. 15 is a side view of Fig. 13 but shows the platform cradle inlowered position with respect to the platform.

Fig. 16 is a detail view of a cylinder guide con- Fig. 18 is a sectionalview taken on the irregular line l8i8 of Fig. 17. This figure also showsthe platform legs in unfolded position extended below the platform.

Fig. 19 is a detail view of a latch device shown in Fig. 17.

Fig. 20 is a diagrammatic view ofthe winch mechanism for operating thecables whereby the platform is withdrawn into the cradle afterunloading.

Figs. 21 to 23 illustrate diagrammatically the use of the dischargingplatform in connection with a low lift truck.

Fig. 24 is a diagram showing the use of the platform with a high lifttruck.

Fig. 25 is a diagram showing how the platform may be used as a palletand load pick up device.

Fig. 26 illustrates a device shown in Fig. 25

for separating stacked packaged merchandise.

In Figures 1 to 5 the reference numeral 2n denotes an industrial truckwhich is equipped with a load raising and lowering mechanism comprisingflxed guides 2i and a lift 22 which moves up and down between theguides. The lift carries pick up forks 23. A load push oil device 28 isalso carried by the lift. The packaged material 2| is in known mannersupported on pallets 25.

. The unloading device according to this invention comprises a platform21 which is carried in a cradle-26. The cradle is supported on the liftto move therewith and is also capable of an independent vertical andswinging movement as will appear hereinafter. Figs. 1 to 5'illustrate'the operation of the truck, constructional details beingomitted.

40 InFIgJthetruckhaspickedupaloadedpal let on the forks 23. The cradle26 with the platform 21 are carried in their neutral positions upon thetruck. In Fig. 2 the truck has arrived in front of a stack of loads 2|which have been previously unloaded from pallets. The cradle 25 has inthisflg'lll'e been moved down below the pallet and the platform has beenexpelled from the cradle and is now resting upon an unloaded package 24of material. Inasmuch as the upper surface of the pallet 25 is at ahigher level than the platform surface, it is necessary that the palletand load be lowered in order that the load may be moved smoothly fromthe pallet to the platform. This situation is shown in P18. 3. Here tothe loaded pallet and the cradle have been lowand the platform are nowat the same height.

Theload is .now transferred to the platform-by Operation of the push ofldevice 28 as shown in Fig; 4. Fig. shows the load finally deposited uponthev platform 21. v The latter is now pulled out from underneath theload and withdrawn within the platform by a suitable winchmechanism H3.The cradle and platform are thereafter moved back into neutral positionupon the 4 from the vertical neutral position in Fig. 9 to thehorizontal unloading position shown in Fig.

11. See also Fig. 2. This 90 degree movement from vertical to horizontalis accomplished by the following means. The pivot shaft 36 carries alever 56 which is connected by a link 61 with an inclined lever 53pivoted on the fulcrum 46 and truck which may then drive away foranother held in upright neutral position. From the latter load. In theforegoing operation no manual labor has been employed except that of thetruck driver. It will be observed that the pallet 26 in Fig. 5 no longercarries a load. The pallet may therefore be removed for use with anotherload.

If, for example, the packaged material is unloaded into a railroad carfor shipment to a distant point, the pallets are not tied up with suchshipments but may be used immediately for other purposes.

If the material is to be unloaded upon the floor a somewhat differentoperation is necessary. This is illustrated in Figs. 6 to 8. In Fig. 6the loaded truck has arrived at the unloading point and the platform hasbeen expelled from the eradle. In order to raise the platform to receivethe load collapsible legs 30 carried by the platform are automaticallyunfolded below the platform for its support upon the floor. Then thepallet and the load are lowered to platform level as in Fig. 3 and theload is transferred to the platform, Fig. 7. The platform now collapsesunder the weight of the load. When thereafter the platform is pulled outfrom underneath the load, the latter will remain deposited upon thefloor, Fig. 8.

Referring now to Figs. 8 to 12 the cradle 26 which carries the platformis shown as being provided with lugs 3| secured to a rotatable pivotshaft 36 carried in acradle arm 36. The arm 36 is secured to the pistonstem 31 of a piston 36 which is hydraulically operated within a cylinder33, Fig. 12. The cylinder is mounted upon a main supporting plate 32which is secured to the lift 22, Figs. 9 and 10. The plate 32 carriesthe cylinder mechanism 39, the pick up forks 23 and the load push offdevice 23. The latter may be in the form of a hydraulically operatedtelescopic piston 33 moving within a cylinder and carrying a pusher head34. The cylinder 33 is supported within a cam sleeve 46 which has a cam4| reaching 180 degrees around the cylinder. The cam port for a freelyrotatable bearing 44 which has an upstanding arm 45 forming a fulcrum at46. The cradle arm 36 has an upright key arm 41 with a vertical key 43which slides in akeyway 43 in the rotatable bearing 44. The key arm 41carries a cam roller 53 which runs in the cam slot 4|. The arm 41 alsocarries a pin 62. When power is applied to move the piston 36 down, thepiston stem descends and the cradle arm 36 will be moved down from theposition shown in Fig. 9 to that shown in Fig. 11. As the cradle armmoves down, th key 43 slides down in the keyway 49 and at the same timethe cam roller 53 runs down in the fixed cam slot 4|. The result ofthese movements is that the cradle arm is loweredand also moved around180 degrees to the position shown dotted in Fig, 10.-

. During this lowering and swinging movement of the cradle arm 36, thecradle itself is moved having a nose 53 which rests upon the abovedescribed pin 52. In Fig. 9 the pivot shaft 36 cannot be rotated becausethe lever 56 cannot swing about the point 46 and the cradle is thereforethe cradle is swung in to horizontal unloading position by the combinedactions of the lever 63. the link 51 and the arm 66 whereby the shaft 36is rotated degrees. As the fulcrum 46 is moved horizontally through anarc of degrees and the pin 52 is lowered away from the nose 66 on thelever 56, 51 and 66 have a combined cooperative movement whereby theshaft 35 is rotated to lower the cradle and the parts come to rest inthe dotted position shown in Fig. 10. The cradle is stopp d in unloadingpontion by a stop finger 63 on the shaft 36 which moves in under theeradle arm and prevents further rotation of the shaft 35.

The platform is expelled from the cradle by an expelling mechanism shownin Figs. 13 and 14. The cradle is in the form of a trough 26 having asolid bottom and sides 63, 63. Cross braces as at 64, 64 are provided tostrengthen the construction. The cradle contains a platform pusher head66 which is moved back and forth by piston arms 66 which move inhydraulically operated cylinders 61. The arms are pivoted to the pusherhead at 66, 63. The cylinders are pivoted to the cradle at 63, 66. Thecylinders are connected in mutual sliding relation by a cylinder guideconsisting of two rings 13, III which are pivoted together at l I, Fig.16. The cylinders pass freely through the rings.- When power is appliedto the cylinders through a suitable hose connection 12, the piston armsare forced out of the cylinders to move the pusher head outward to expelthe platform The normal inner position of the pusher head is shown indotted lines.

The platform, Figs. 17 and 18, is in the form of a wedge shaped hollowbox having a flat top 33. The rear end 6| is closed so that it may beengaged by the pusher head 66. Thecollapsible leg mechanism hereinabovereferred to comprises the following elements. The platform can'ies fourlegs. Each leg consist of a pair of upper links 82 and a pair of lowerlinks 33. The two front legs are pivoted on a transverse shaft 34supported on the. platform. The two near legs are pivoted on atransverse shaft 66. The links in the front legs are hinged together bya shaft 36. The links in the rear legs are hinged together by anothershaft 81. The hinge shafts 36 and 31 move up and down freely as the legsare unfolded and collapsed. Springs 33 and 36 urge the unfolding of thelegs in the directionof the arrows in Fig. 18'. The legs are stopped inunfolded positions by stops at 90 and 3|. Normally the legs are held incollapsed position within the platform by swinging latches 92, Fig. 19,which are urged in under the legs by prings-l3. The latches are When thelatches 02 are released the legs unfold automatically by the action ofthe springs 08 and 89. The legs are caused to collapse by means of theplatform withdrawing cables I5 which are operated by a winch mechanismto be explained hereafter. There is a cable IS on each side of theplatform. The platform ends of the cables are attached to the hingeshafts and 01 at the points IOI, Fig. 17. The one cable runs from thepoint IN on shaft 06 over the idler sheaves I02, I03 and I04 and thenback out from the platform. The other cable 15 runs from the point IN onthe shaft 01 over the sheaves I02 and I05 and then out from theplatform. Each cable carriesa fixed stop I06 adapted to engage fixedbraces I0'I in the platform, respectively.

The free ends of the cables leading out from the platform pass overguiding pulleys and sheaves to a power winch IIII, Fig. 10, which ismounted on a supporting plate III secured to the rear side of the lift22. The winch has two cable drums H2 and H3. The cables I5 pass from theplatform over guide pulleys III and cable sheaves H5 and H6 to the cabledrums. These latter are operated as follows, see Fig. 20. The winch IIOrotates the cable drum shaft II! as usual. to the shaft by a hydraulicclutch H8 and the shaft may be locked by a brake H9. A coiled powerspring I has one end connected to the shaft and the other end isconnected to the drum. In the neutral upright position of the cradle andplatform as in Fig. 9 the two cables I5 pass from the cable drums overthe sheaves II 6 and H5, guiding pulleys Ill and then up to the platformwithin the cradle. The cables are kept taut because at this time thedrum springs I20 tend to wind up the drums with the cables thereon, theclutches being out and the brakes on, it being understood that theconstruction in Fig. 20 is duplicated for the other cable drum H3. Thesprings I20 are powered to wind up the cables so long as there are freecable lengths to be wound upon the drums. The clutches are operated by ahandle I22, Fig. 10. The brake or brakes H9 may be hand or footoperated, no special mechanism being shown. Inasmuch as hydraulicwinches, clutches, brakes, cable drums and the like are ordinaryarticles of trade it is thought that the foregoing description and theillustration shown are suilicient for understanding the invention.

A hydraulic power supply pump unit of any known type I Fig. 10, suppliesthe power for the hydraulically operated units. The pump has four hoselines of which the line I2 leads to the cylinders 61 in Fig. 13; theline I2'I connects with the push off unit 20; the line I28 may connectwith the winch I I0 and the line I29 supplies the cylinder 39 in Fig.12. The hose connections are made in the usual manner known to the artfor proper operation as will be understood.

The hose 12 extends from the pump forwardly up over and around a shaftI30 which carries the pulleys I and thence upwards to the cradle. Thehose connections are severally valve controlled as shown. All partswhich are to be manually operated by the truck driver are suitablypositioned so as to be within convenient reach. I

Operation: Assuming that a load of packaged material is to be unloadedand deposited at a level above floor level, the operation is as follows.when the truck arrives at the point of unloading the truck driveroperates the lift 22 to bring the The drum I I2 is adapted to beclutched loaded pallet to the proper level with respect to the loadreceiving surface as indicated in Fig. 2. The driver then connects thehydraulic pump with the main operating cylinder 20 which causes thecradle 26 with the platform 21 to be moved down into unloading positionin front of the truck underneath the pallet. Fig. 11 shows the unloadingposition of the cradle below the forks 23 which carry the pallet. Thelatter is not shown in this figure. During this movement the drumsprings I20 will rotate the drums to wind up the two cables 15. The drumIII will of course operate longer than the drum 2 because of the greaterlength of cable to be wound on that side. The drums are unclutched fromthe winch shaft and the brake is on.

Then the pusher cylinders 01 in the cradle are operated and the pusherhead 05 engages the platform and pushes it out from the cradle. Duringthis movement the cables I5 unwind from the cable drums which in turnunwind the springs I20. The platform and cradle are now in the positionsshown in Figs. 13 and 14.

Thereafter the lift is operated to lower the pallet into alinement withthe platform, the cradle being lowered at the same time, Fig. 15. Thelowering of the cradle causes a tightening of the cables I5 which servesto pull the platform against the pallet. The platform may have lugs TIto engage notches I8 in the pallet whereby to lock these elementstogether to facilitate the transfer of the load from the pallet to theplatform. The load is then transferred by operating the push off device20 and thereafter the lift is again operated to lift the cradle intoalinement with the platform.

The pressure in the cylinders 61 having been released the cable drumclutches are thrown in and the winch started to rotate the drums andwind up the cables 15. The stops I06 on the cables engage the braces I01on the platform to pull the latter back into the cradle. The platform inits return movement engages the pusher head i5 and moves it back intothe cradle. The pusher head has cable guides at Ii, Fig. 15, to keep thecables from snarling. When the platform is entirely withdrawn power isagain applied to the cylinder 39 to operate the cradle and platform backinto upright neutral positions. At this time the drum clutches arethrown out and the brakes applied so that as the platform moves backinto upright position, the cables I5 unwind against the force of thesprings I20 and are kept taut.

When the platform is to be used as a collapsible platform the operationis as follows. Before moving the cradle and platform down into unloadingposition, the legs are released from the latches so that the legs willbe ready to unfold by the action of the springs 00 and I! as soon as theplatform has moved sufficiently out from the cradle to permit suchunfolding. The truck driver seizes the grip 00 which is attached to theend of the cable 95. The grip Projects from the side of the cradle. 9. Aslight pull on the cable moves the latches away from the legs and thelatter immediately are now moved outward past the latches and pressedagainst the bottom of the cradle. The driver now lets go of the grip 06and the cable is pulled back by a spring [50, Fig. 17, so that thelatches may again be operated to engage the legs.

The cradle and platform are now moved down into unloading position andas soon as the platform has been sufficiently expelled the legsautomatically unfold under the action of the springs 7 II and 80. Thefront legs will'unfold first and then the rear legs. The unfolding ofthe legs causes a lengthening of the cables II sunicient to spaoe stopsI on the cables a short distance away from the braces Ill. The load isthen transferred from the truck to the platform. Thereafter the driverthrows in the clutches on the winch which is operated to wind up thecables Iii suiilciently to pull the legs of! center position so thatthey will collapse under the weight of the load. The platform is loweredslowly under the load because the collapsing movement of the legs isgradual due to the dash pot action of the cyl- I independent unloadingdevice apart from the truck in the manner illustrated in Figs. 21 to 23.

In these figures a low lift industrial truck I50 has picked up a loadIll supported on a skid I 52 and has arrived at the unloading point,Fig. 21. The platform 21 is then placed upon the floor and connected tothe truck by a chain I53. -The load is then pushed off the skid and ontothe platform,,l"ig. 22. Thereafter the platform is withdrawn from underthe load. This is accomplished by placing'a bracing element I55 betweenthe load and the truck and then connecting the platform to a winch I56by a cable I51, As the cable is wound up the platform is pulled out fromunder the load. Fig. 23 shows the truck turned parallel to the loadbecause in practice it will often be found necessary to do so because oflimited space in handling and loading packaged merchandise. The use ofthe platform in connection-with a high lift truck I60 is shown in Fig.24.

In the foregoing disclosure the platform 21 has been described and shownas an unloading device. It may, however, also be used as a load pick updevice or be used to replace pallets. Thus, for example, packagedmerchandise may be divided-into suitable load units by means ofseparating boards I02 as shown in Fig. 25. -Such boards will provide aspace or pocket between load units for. the entrance of the thin edge ofthe platform 21. The platform will be carried directly upon the forks 23of the truck 20. As the truck drives forward the platform will besqueezed in between the load units as will be understood. After theplatform has been moved in between the loads, the platform with the loadwill be raised 01! the stack and moved to another point. Here theplatform may be lowered to unloading level and then withdrawn. fromunder the load. If, for example, packaged merchandise is stacked in arailroad car for shipping, the loads units may be separated as shown foreasy unloading at the point of destination by means of fork trucks. Thusthe expensive pallets are not used for trans.- port.

I claim:

1. In an industrial fork truck, a mechanism for unloading merchandisesupported on a pallet carried by the fork on the truck comprising amovable cradle, an unloading platform slidably supported within thecradle, means for supporting the cradle on the truck in a normalinoperative position, means for moving the cradle into an unloadingposition underneath the said pallet, means within the cradle for movingthe platform out of the cradle to a load receiving position in front ofand level with the pallet, means on the truck for transfen'ing the loadfrom the pallet to the platform, means on the truck for withdrawing theplatform from underneath the load and means on the truck for moving thecradle back into its said inoperaive position on the truck.

2. In an industrial truck, an unloading mechanism comprising avertically and horizontally movable cradle, hydraulic means on the truckfor moving said cradle from a vertical inoperative position to ahorizontal unloading position. an unloading platform slidably supportedwithin said cradle, hydraulic means within said cradle operativelyconnected to said platform for expelling the latter from the cradleafter the cradle has been moved into its said unloading position, meamfor transferring a load from the truck to the said expelled platform,means on the truck for moving the platform away from underneath the loadand back into the cradle and means for actuating the said cradle movingmeans to move the cradle back into its said vertical position.

PREBEN J ESSEN.

